Full circle sprinkler



Dec. 22, 1936.

W. VAN E. THOMPSON FULL C IRCLE SPRINKLER Filed Jan. 28, 1935 //v Z/C'N 7'02 Msm r52 MN 5 Tin/72mm Patented Dec. 22, 1936 UNITED STATES PATENT OFFICE FULL CIRCLE SPRINKLER fornia Application January 28, 1935, Serial No. 3,814

Claims.

My invention relates to irrigation sprinklers, and particularly to the type of sprinkler in which the water is rotated in a chamber and is caused to: flow through an outlet opening, whereupon the Water spreads outward to cover a circular area.

The sprinkler heads of most sprinklers of this type consist essentially of a casting directly connected to a supply pipe delivering water into a relatively enlarged delivery chamber formed in the casting in which is provided means for causing the water to fiow in a circular path within the chamber, there being also a relatively small delivery orifice formed in a thin upper wall of the casting and communicating with the delivery chamber through which water is forced under water-main pressure.

One of the most noted disadvantages of sprinkler heads of the ordinary type is that it is impossible to get an even distribution of the spray over given areas from minimum to maximum range. In my experiments with this type of sprinkler head I have found that as the volume of water delivered through the supply pipe is increased to enlarge the area covered by the sprinkler, the water tends to break up into smaller drops as the velocity is increased so that at the maximum velocity obtainable from the watermain the water is delivered from the orifice in a fine spray. Above a certain point an increase in 30, volume and velocity defeats the purpose for which the volume is increased; namely, an enlarged area, because the individual drops of the atomized water have insufiicient weight to carry over a greater distance although their velocity upon leaving the orifice is high. This ordinary type of head when operating at or near maximum volume and velocity gives poor distribution especially when operating in wind, for the reason that the individual atomized drops lack sufficient weight to have any appreciable carrying power against even a moderate wind, and may be blown so that all of the water is carried off to one side of the sprinkler.

It is a general object of my invention to provide a sprinkler head capable of covering a greater area with less water and with a more even distribution.

It is another object of the invention to provide a sprinkler head operable to break the water up into individual drops of sufilcient size to efiect an increased range and an even distribution of water even when operating in a wind.

I have found that placing within the delivery chamber a projection which extends upward from the bottom of the chamber and terminates just below the outlet orifice in such a manner as to provide a. restricted annular passage through which the water must pass before it enters the delivery orifice results in a pronounced increase in efficiency with respect to range and distribution 5 for a given volume of water over the ordinary type of sprinkler head described above.

The tests that I have made show that my device will give an improved distribution over a given area with a smaller volume of water at considerably lower pressure. For instance, an ordinary type of stationary sprinkler head covered a 17' diameter area using 2 gallons of water per minute at 12# head pressure, while with my sprinkler a 17' diameter area was covered with improved distribution using 1.75 gallons of water per minute at 7.5# head pressure.

The restricted passage formed by the projection acts to increase the velocity or the water just prior to the time it fiows into the delivery orifice. This increase in velocity creates a region of low pressure into which the water flows before it enters the discharge orifice. This increased velocity and reduction in pressure prior to discharge through the orifice is, I believe, directly effective to accomplish a more eificient breakingup of the water as it flows from the orifice, resulting in increase-d range and superior distribution for a given volume of water over the ordinary type of sprinkler head.

It is therefore an object of the invention to provide a sprinkler head including a means within the delivery chamber for increasing the velocity of the water just prior to its discharge through the discharge orifice.

It is another object of the invention to provide a sprinkler head including means within the delivery chamber for releasing the pressure on the water just prior to its discharge through the discharge orifice so that pressure is transformed to velocity.

It is another object of the invention to provide a sprinkler head of the character described having an annular restricted passage formed within the delivery chamber through which the water fiows before its discharge from the outlet orifice.

Aside from the above it is also possible that the increased range and improved distribution may be due partially to a reduction of turbulence within the chamber in the region directly below the discharge orifice. The central projection provides a definite annular channel in the chamber around which the water flows in an upward spiral through the restricted passage and into the discharge orifice, the projection preventing any 55 of the water from flowing upward at the center of the chamber directly below the discharge orifice which I believe results in a definite reduction of turbulence within the chamber thus reducing to a minimum the amount of energy dissipated by turbulent flow. This reduction of turbulence is effective to cause the water to be broken up into drops of larger size having greater carrying capacity thereby increasing the range of the sprinkler at given volume and pressure.

It is therefore another object of my invention to provide in a sprinkler having a delivery chamber in which the water is rotated, a projection cooperating with the walls of the chamber to form an annular channel in which the water is caused to rotate.

In connection with the above-stated objects and description of the new mode of operation of the invention, I will show in the accompanying drawing two alternatives illustrating different ways of forming the obstruction in the delivery chamber to provide the annular restricted passage within the chamber which is effective to reduce turbulence and to increase the velocity and lower the pressure of the water before it is discharged irom the outlet orifice. The two forms shown are merely illustrative and the true scope of the invention should be gleaned from a perusal of the following part of the specification and an interpretation of the appended claims in connection with the drawing.

In the drawing,

Fig. l is a vertical section through a sprinkler head comprising one form of my invention.

Fig. 2 is a horizontal section taken as indicated by the line 22 of Fig. l.

Fig. 3 is a fragmentary vertical section taken as indicated by the line 33 of Fig. 2, illustrating a preferred type of delivery port operable to' produce a rotation of the water in the delivery chamber of the invention.

Fig. 4 is a partially sectioned view illustrating another form of the invention.

Referring first to Figs. 1 to 3, inclusive, I show a sprinkler head generally designated by the numeral Hi which in the form illustrated preferably comprises a stationary body II and a movable body generally designated by the numeral |2. The static-nary body consists of a casting provided with an internally threaded recess l3 adapted for securement to a water supply pipe indicated by dotted lines M. The body II is provided with an upward facing cavity l5 provided with internal threads Hi, this cavity being in communication with the supply pipe M by means of an opening l'l substantially in the. manner shown.

The movable body [2 of the sprinkler head Ii) includes a primary or pressure chamber and the delivery chamber which cooperate with various parts of the movable body, which I will now describe, to form the spray means of the invention. Referring to the details of construction of the movable body I provide an externally threaded plug 26 adapted to be threadedly received in the cavity l5 so as to be vertically movable therein. Formed in the plug 20 is a downwardly disposed, preferably circular, cavity, the walls of the plug defining the lower portion of the cavity forming a upper wall 25, the inner surface 23 thereof being preferably tapered, substantially in the manner shown. Formed in the upper wall 25 is a centrally disposed circular discharge orifice 2E. Formed on the upper end of the plug 28 is an upwardly extending annular rim 2?, in which is provided suitable engagement means, such as screw-driver slots indicated at 28, by which the plug may be threaded relative to the stationary body for the purpose of moving the movable body vertically. Adapted to be received into the main cavity of the plug 20 and to abut the annular shoulder 22 in such a manner as to extend across the cavity at an intermediate point is a port-plate 30. Also adapted to be received into the cavity and to abut the peripheral edge of the port-plate 30 is an end bell in the form of a cup 3| preferably provided with an arcuate bottom 32, the end bell serving as a retaining means for the port-plate 38 and also serving as a closure means for the lower end of the main cavity. The end bell or closure means 3| and the port-plate 3i) cooperate with the walls forming the main cavity in the plug to define two chambers, the lower chamber designated by the numeral 33a forming the pressure chamber of the invention which I shall hereinafter term the primary chamber, and the upper chamber 331) with which the discharge orifice 25 communicates will be hereinafter termed the delivery chamber of the invention. As indicated at 35 in Fig. 1, the lower end of the depending skirt 2| of the plug 20 is swedged inwardly around the cup 3| after it is inserted in the cavity for the purpose of permanently retaining the cup 3| and the port-plate 30 therein.

Provided in the closure member 3| is a plurality of openings 36 through which water may pass from the cavity i5 of the stationary body which communicates with the supply pipe I4 into the primary chamber 32. The central portion 31 of the closure member 3| is adapted to serve as a valve member which engages the opening H in the lower wall of the cavity |5 when the plug 2|] is threaded downward, thus the volume of water passing through the opening I1 may be regulated as desired by a manipulation of the plug 2|] in a manner which will be readily understood.

Communicating ports are provided in the portplate 3%! for delivering water from the primary chamber into the delivery chamber. I prefer that the water thus delivered into the delivery chamber be caused to rotate therein and for this purpose I preferably provide a plurality of ports which, as best shownin Figs. 2 and 3, are stamped from the metal of the port-plate so as to provide elongated passages 40 which are disposed helically with respect to the central axis of the delivery chamber so that the water is swirled as it passes through these ports promoting an annular or rotating flow of the water within the delivery chamber.

My invention includes a means for increasing the velocity of water just prior to its entrance into the discharge orifice, which creates a region of low pressure through which the water passes just prior to its discharge. This means comprises walls forming a restricted passage through which the water must flow before it enters the discharge orifice. I prefer to form this restricted passage by providing a projection which extends across the delivery chamber'and terminates in spaced relationship with the delivery orifice to form the restricted passage. As shown in Fig. 1, this projection may be provided by stamping the central portion of the port-plate upward. to form a projection 45 which in this form of the invention is preferably cylindrical and of substantially the same diameter as the orifice 26, the upper peripheral edge 46 of the projection 45 cooperating with the wall of the orifice 26 to form an annular restricted passage 4'! through which the water must flow before it enters the discharge orifice. The projection 45 also provides a means for guiding the water in the delivery chamber in an annular or rotating flow, the projection cooperating with the walls of the chamber to provide an annular channel around which the water flows as indicated by arrows A of Fig. 2. The projection 15 by defining the above-mentioned annular channel around which the water flows acts to prevent the creation of turbulence within the chamber in the region in which turbulence normally occurs directly below the discharge orifice, and by diminishing the turbulence of fiow within the delivery chamber reduces the amount of energy which would normally be dissipated by turbulence, thus increasing the range of the sprinkler at a given volume and pressure.

The increase in velocity and the reduction in pressure of the water just prior to its discharge through the discharge orifice is effective to break substantially all of the water into individual drops of sufiicient size to have increased carrying power against wind, thus giving greater range and better distribution of the water.

With reference to Fig. 4 in which I show a second form of the invention, I prefer to provide the projection 45 with a conical upper surface 59. As shown in Fig. 4, the conical surface 50, in cross section, is angled in a plane A-A which is preferably substantially perpendicular to the shortest plane between the peripheral edge of the orifice 26 and the surface 59, this plane being indicated by the line B. I have found that this form of projection gives slightly improved performance with respect to the form already described for given volume and pressure. It will be noted from an inspection of Fig. 4 that in this form I have shown the lower cylindrical portion 5! of the projection slightly smaller in diameter than the discharge orifice 26, and have shown the apex 52 of the conical surface 55! substantially in the plane of the lower edge or entrance of the orifice 26, the area of the restricted passage 4i being substantially the same in both forms.

I believe that the improved performance effected by the second form of projection over the first described form for a given volume and a given pressure may be attributed to two factors; first, the directional effect that the conical surface 50 has upon the water delivered through the orifice 26, and, second, the still further reduction of turbulence within the chamber in the region adjacent the orifice, thus decreasing to a minimum the amount of energy dissipated by turbulence in the fiovving water. By definitely directing the fiow of water through the orifice at a certain critical angle, the delivery of the drops to the desired point in the circular area covered by the sprinkler is accomplished.

It should be understood, however, that I do not wish to imply that the relative diameters of the projection 55 and the orifice 26, or the area of the restricted passage 41 in either of the two forms shown, or the exact location of the apex 52 of the conical surface 59 in the form shown in Fig. 4, are critical to the extent that they are essential to the new mode of operation effected in my invention.

The provision of the projection extending across the delivery chamber forming the annular chamber around which the water is guided in an upwardly spiralling annular path, and forming the annular restricted passage through which the water flows prior to its discharge from the orifice which is effective to increase the velocity and lower the pressure of the water prior to its entrance into the discharge orifice, comprises, in combination with the other elements illustrated in the sprinkler head, a new combination of elements having a new mode of operation and effecting a new result; namely, increased range and improved distribution for a given volume at a given pressure.

I am aware that various modifications of the projection or its equivalent might be provided within the delivery chamber whereby the new mode of operation might be effected to obtain substantially equally good new results, these modifications, however, coming within the true scope of the invention interpreted by the appended claims.

I claim as my invention:

I. In a sprinkler head, the combination of a body having walls forming a delivery chamber; walls forming a discharge orifice in said body communicating with said chamber; a projection extending into said chamber concentric with said orifice and terminating in an upper face in spaced relationship with the walls forming said orifice,

said surface lying substantially perpendicular to the shortest plane between the peripheral edge of said orifice and said face; and means for delivering water into said chamber in a rotating flow around said projection.

2. In a sprinkler head, the combination of: a body having walls forming a primary chamber and a delivery chamber, said primary chamber communicating with a water supply pipe; walls forming a discharge orifice in said body communicating with said delivery chamber; walls forming communicating ports between said chambers and disposed to cause the water delivered therethrough to rotate in said delivery chamber; and walls forming a projection extending across said delivery chamber concentric with said discharge orifice and cooperating with the walls of said delivery chamber to form an annular channel around which the water flows, said projection providing an upper surface formed to direct the water flowing from said orifice substantially perpendicular to the shortest plane between the peripheral edge of said orifice and said surface.

3. In a sprinkler head, the combination of: a body having walls forming a delivery chamber; walls forming a discharge orifice in said body communicating with said chamber; a projection extending into said chamber concentric with said orifice and terminating in an outer surface formed to direct the water flowing from said orifice substantially perpendicular to the shortest plane between the peripheral edge of said orifice and said surface; and means for delivering water into said chamber in a rotating fiow around said projection.

4. In a sprinkler head, the combination of: a body having walls forming a delivery chamber; walls forming a discharge orifice in said body communicating with said chamber; a projection extending into said chamber concentric with said orifice and terminating in an outer surface which is angled in cross section to lie in a plane substantially perpendicular to the shortest plane between the peripheral edge of said orifice and said surface; and means for delivering water into said chamber in a rotating flow; around said projection.

5'. In a sprinkler head, the combination of: a body having walls forming av delivery chamber; walls forming a discharge orifice in said body communicating with said chamber; a projection extending into said chamber concentric with said orifice and terminating in an'outer conical surface substantially perpendicular to the shortest plane between the peripheral edge of said orifice and said surface; and means for delivering water into said chamber in a rotating fiow around said projection.

6. In a sprinkler head, the combination of: a body having walls forming a delivery chamber; walls forming a discharge orifice in said body communicating with said chamber; a projection extending into said chamber concentric with said orifice and having an outer conical surface substantially perpendicular to the shortest plane between the peripheral edge of said orifice and said conical surface, said conical face having an apex lying substantially in the plane of the inner peripheral edge of said orifice; and means for delivering water into said chamber in a rotating flow around said projection.

'7. In a sprinkler head of the class described, the combination of: walls forming a delivery chamber, and having top, side, and bottom walls, there being a discharge orifice in said top wall, and a plurality of water-swirling port means through which water is introduced into said delivery chamber in a swirling condition; and a fixed projection extending toward said discharge orifice and having a wall cooperating with the portion of said top wall surrounding said discharge orifice to form an invariable annular restricted passage which increases the velocity, and decreases the pressure of the water which fiows thereinto in an inwardly swirling direction.

8. In a sprinkler head of the class described, the combination of: walls forming a delivery chamber, and having top, side, and bottom walls, there being a discharge orifice in said top wall, and. a plurality of water-swirling port means through which water is introduced into said delivery chamber in a swirling condition; a fixed projection extending toward said discharge orifice and having a wall cooperating with the portion of said top wall surrounding said discharge orifice to form an invariable annular restricted passage; and flow-regulating means for regulating the flow of water into said delivery chamber, and being operable without disturbing said projection or its relative position in said delivery chamber.

9. In a sprinkler head of the class described, the combination of walls forming a delivery chamber, and having top, side, and bottom walls, there being a discharge orifice in said top wall, said top wall having an inner surface which is conical in contour and inclines upward to said discharge orifice, and a plurality of water-swirling port means through which water is introduced into said delivery chamber in a swirling condition; and a fixed projection extending toward said discharge orifice and having a wall cooperating with the projection of said conical surface of said top wall surrounding said discharge orifice to form'an invariable annular restricted passage which increases the velocity and decreases the pressure of the water which flows thereinto in an inwardly swirling direction.

10. In a sprinkler head of the class described, the combination of 1 walls forming a delivery chamber, and having top, side, and bottom walls, there being a discharge orifice in said top wall, said top wall having an inner surface which is conical in contour and inclines upward to said discharge orifice, and a plurality of water-swirling port means through which water is introduced into said delivery chamber in a swirling condition; a fixedprojection extending toward said discharge orifice and having a wall cooperating with the portion of said conical surface of said top wall surrounding said discharge orifice to form an invariable annular restricted passage;

WALTER VAN E. THOMPSON. 

